Resilient support for photo-electric cell exciter



April 1933- w. H. BA'UCH 1,904,038

RESILIENT SUPPORT FOR PHOTO-ELECTRIC CELL EXCITER Original Filed Jun 25, 1930 INVENTOR. "(/44 mm b. B/wcw.

W Raw! A TTORNE Y.

Patented Apr. 18, 1933 UNITED STATES P ATE NT OFFICE WILLIAM H. BAUGH, OF SHELBYVIIJLE, INDIANA, ASSIGNOR 'I'O SON O EQUIPMENT COR- PORATION, 0F INDIANAPOLIS, INDIANA, A CORPORATION REsI'LInnm snrron'r non rnoro-nnncrnro CELL EXCITER Application fi1ed June 23, 1930, Serial No. 463,037. Renewed September 16, 1932.

This invention relates to a mounting for an exciter bulb to beused inconnection with a photo-electric cell. The invention is particularly applicable to an apparatus used for reproducing sound from so-called sound films.

In ordinary use an exciter bulbis apt to be subjected to vibrations from exterior causes, such as the engagement of gears the projecting apparatus. Such vibrations, when imparted to the filament of the exclter, are transmitted in the form of light variations to the photoelectric cell. \Vhen the vlbration has a frequency falling within the sound wave band a corresponding sound issues from the reproducing apparatus.

The principal object of this invention is to provide a mounting for such bulbs, by means of which these vibrations are not transmitted to the filament.

The principal feature of the invention by which this object is obtained is the provision of a resilient support for said bulb. Such a support has in itself a natural period of vibration, depending upon its resiliency. If this period of vibration does not coincide with that of mechanical vibrations from within or without the device, these vibrations are not transmitted to the filament. If the natural frequency of the support does coincide with that of exterior vibrations, the said support vibrates in resonance therewith causing the same to vibrate and producing greatly increased sounds in the amplifier.

By means of another feature of the invention, means are provided by which the not ural period of vibration of the support may be varied at will so that it may be adjusted not to coincide with that of the exterior vibrations.

Another feature of the invention resides in the provision of means by which this variation of natural frequency is accomplished without substantial variations in the position of the exciter filament.

The features of the invention by which these and other objects are attained will be apparent from the accompanying drawing and the following description and claims:

Fig. 1 is a plan view of an exciter bulb support embodying the invention. Fig.2 is a side elevational view thereof. Fig. 3 isa front elevational view. Fig. 4 is a side elevational View of a portion of the apparatus as shown in Fig. 2.

The exciter mounting includes a base meiiiber 10 having two parallel openings 11 therein. The said openingsare adapted to engage pins 12 carried uponany suitable support 13. A thumb screw 14: engages one of the pins 12 for maintaining the base member thereon in fixed position. At'oneendofthe base member 10 there is fastened a downwardly-extending L-shaped member 1 5 offi esilient material, to the lower end of which is fastened a horizontal bulb-supporting member 16. The member 15 acts as a resilient hinge support for said bulb-supporting member 16. A'b'ulb socket 17 has, a downwardly-extending threaded shank 18 passing through an elongated opening 19 in the bulb-supporting member 16. Adjusting nuts 20 threadeclly engage the shank 18 on either side of'the bulb-supportingmember 16 and serve for vertical adjustment of the socket 17. The socket 17 carries a lamp '2 1.

7 At the opposite end of the base member 10, a downwardly-extending portion 22 has fastened theretofa leaf spring member 23, said "member extending 'over the end of the bulb-supporting member 16 and earryingfa thumbs'cr'e'w 24 pas'sing through an o'ening therein. The screw 24 has a hea 2 5 engaging the upper surface of the 23 and the shank thereof threadedlyengages the bulb-supporting member 16. The'sp'ri'n'g' 2-3 and screw 24, therefore, form 'a resilient support for the otherwise free end of the bulb-supporting member 16. A second leaf spring 26 is also fastened to the portion 22 of the base member and engages the upper surface of the bulb-supporting member 16, exerting a downwardpressure thereon.

The springs 23 and 26 exert opposing forces upon the bulb-supporting member 16, the spring 23, tending to support the said member and the spring 26 urging said member downward. The tension upon these springs, therefore, determines the natural period of vibration of the bulb-supporting member 16 upon its supports. By changing the adjustment of the thumbscrew 24, this frequency may be varied to bring it out of harmony with the frequency of exterior vibrations. By this means a large amount of extraneous noise in the amplified sound is prevented.

It will be noted that the spring 23 is relatively longer than the spring 26. Because of the length of the spring 23, a relatively large displacement thereof, by operationof thescrew 24, will cause only a slight displacement of spring 26. The adjustment of the screw 2 f, therefore, does not cause a substantial change in the position of the bulb-sup- & porting member 16.- The adjustment of the filamentposition of the bulb 21 is, therefore, not substantially disturbed by the. adjustment. of the springs23 and 26.

,Various departures may be made in the details of the invention herein illustrated without departing from the broader features thereof as defined by the following claims. a

The invention claimed is: v

1. A mounting for an exciter bulb includ- 1, ing a bulb-supporting member, a flexible support for supporting one end of said bulb-supporting member, a pair of spring members adapted to exert opposing forces upon the opposite end of said bulb-supporting member, and a singleadjusting means for simultaneously varying the tension of said springs, said said bulb-supporting member for exerting a force thereon.

4. A mounting for an exciter bulb includa base member, a bulb-supporting member, a flexible support for supporting one end of said bulb-supporting member upon said base member, a leaf spring fastened to said base member and extending to a point above the opposite end of said bulb-supporting member, ascrewpassing through an opening in the extending portion of said spring and having its head in contact withthe upper surface thereof and its shank threadedly engaging said bulb-supporting member. for supporting the same, and a second leaf spring fastened to said base member and having a portion'in contact withthe upper surface of said bulbsupporting member for exerting a force thereon, said springs beingproportioned in size and strength so that movement of said screw deflects said springs without substantial movement of said bulb-supportingmember. In witness whereof, I have hereunto aflixed my signature. 7 v y p WILLIAM H. BAUCH. j

springs being proportioned inwsize and strength so that movement of said tensionvarying means deflects said springs without substantial movement of said bulb-supporting member. 7

2, A mounting for an exciter bulb includin'g'abulb-supporting member, a hinged support for supporting one end of said bulbadapted to exert opposing forces upon the supporting member, a pair of spring members opposite end of said bulb-supporting member, and a single adjusting. means for simultaneously varying the tension of said springs,

. said springs being proportioned in size and strength so that movement of said tensionvarying means deflects said springs without substantial movement of said bulb-supporting member.

3. A mounting ing a base member, a bulb-supporting member, a flexible support for supporting one end for an exciter includof said bulb-supporting member upon-said 6 base member, a leaf spring fastened to said base member and extending to a point above the opposite end of said bulb-supporting member, a screw passing through an opening in the extending portion of said spring and having its head in contact with the upper surface thereof and its shank threadedlyengaging said bulb-supporting member for supporting the same, and a second leaf spring fastened to said base member and having a portion in contact with the upper surface of 

